The subject matter disclosed herein relates to radiation detection techniques and systems and, more particularly, to the detection and correction of signals using such systems.
In single photon emission computed tomography (SPECT) imaging and positron emission tomography (PET) imaging, a radiopharmaceutical is administered to a patient. The radiopharmaceutical is typically selected so as to be preferentially or differentially distributed in the body based on the physiological or biochemical processes in the body. For example, a radiopharmaceutical may be selected that is preferentially processed or taken up by tumor tissue. In such an example, the radiopharmaceutical will typically be disposed in greater concentrations around tumor tissue within the patient.
In SPECT and PET imaging, gamma rays are generated when the radiopharmaceutical breaks down or decays within the patient. These gamma rays interact with detection mechanisms within the respective PET or SPECT scanner, which allow the decay events to be localized, thereby providing a view of where the radiopharmaceutical is distributed throughout the patient. In this manner, a caregiver can visualize where in the patient the radiopharmaceutical is disproportionately distributed and may thereby identify where physiological structures and/or biochemical processes of diagnostic significance are located within the patient.
The mechanism used to detect the gamma rays may include a conversion material which, when impacted by the gamma rays, generates an electrical charge that may be detected by electrodes proximate to the conversion material. The detected charges, which provide information about the location, energy, and timing of the gamma ray impact events, may in turn be used to generate images of the patient or other object undergoing imaging.
However, due to structural considerations related to the detector, in certain circumstances charge information may be lost. For example, due to the segregation of a detector into various unit areas of measurement or read-out, e.g., pixels, gamma ray impacts that occur generally between two or more pixels may go undetected or may otherwise undergo loss of some of the charge information that would otherwise contribute to the imaging process. Loss of this charge information may result in reduced or degraded performance of the imaging system.